I have been experiencing bad battery life on my less than 2 week old 3GS and have decided to try to work out why it is not performing well rather than taking it back and possibly experiencing the same thing again. I am a first time iphone user and therefore do not have any point of reference for older models battery life however my iphone would not make it through one work day (8 hours) with low - moderate usage without losing over 50% battery life. Last night I charged the phone from dead (phone turned itself off) to full battery and I even left the charger plugged in for an extra 3-4 hours after it was 100% to "calibrate" the battery. At midnight I unplugged the phone and turned the following off: 3G off, push off (turned it off in advanced options too), bluetooth off, location services off, wifi off. I then reset the phone and went to sleep leaving it on standby. I woke up this morning (8.15am) and had 95% battery left. What however was interesting was that my phone said it had used 30mins of usage up over the near 8hours of standby time. My question is what is this "usage", i think it could be the fetching of the emails however I have it set to hourly fetches and could 8 fetches really take 30mins of usage? It is now 10.24am and my battery is at 90% and I have barely touched the device (literally touched it a few times to turn the screen on and check the battery % meter). Could this indicate a bad battery? I have been using a friends usage as a point of reference and he seems to get pretty much 2 days solid use out of his phone before it turns off or requires recharging. Apologies for reposting another battery thread but hopefully this one is different because somebody may be able to clarify for me what usage is going on when im asleep and the phone is on standby with all features turned off.